In daily life, pivot mechanisms are widely applied to such articles as doors, windows, rearview mirrors of cars, notebook computers, electronic dictionaries, personal digital assistants (PDAs) and mobile phones. Such an article generally includes a rotating body and a body. The rotating body is rotatable relative to the body through a pivot mechanism. The pivot mechanism generally includes a shaft, a gasket, a stator and a rotor. The rotating body of the article is connected to the rotor such that the rotating body can rotate together with the rotor. As the rotor rotates relative to the stator, the friction force produced between the stator and the rotor is used to counteract the torque force produced by the weight of the rotating body, so that the rotating body can be positioned and held in place by the external force. However, the friction force between the stator and the rotor may too large or too small. If the friction force between the stator and the rotor is too large, the necessary of external force taken to rotate the rotating body also become larger. In the meantime, the pivot mechanism is easily worn out and has a shot service life. In the contrary, if the friction force between the stator and the rotor is too small, the pivot mechanism is loose and the rotating body cannot be efficiently positioned and held in place.
In addition, if the relationship between the components of the pivot mechanism is improper, a counter force is produced between the stator and the rotor during rotating. The counter force drives the rotating body to rotate back when an external force used to rotate the rotating body is removed. Thus, the rotating body cannot be exactly positioned.
Thus, there is a room for improving the pivot mechanism.